Narrative:

Captain flying. We landed on runway 21L at dtw, cleared to hold short of runway 21R on taxiway foxtrot. Switched to south ground; controller says he told us to hold short of runway 21R. I believe I acknowledged the hold short instructions, but not totally sure. However, I continued with my after landing flow. When I looked up we were crossing runway 21R, the captain and I noticed a saab going around runway 21R, after crossing the runway, ground told us to have the captain phone the tower when we got to the gate.

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Original NASA ASRS Text

Title: AFTER LNDG AT DTW, DC9 CREW CROSSED THE PARALLEL RWY AFTER ACKNOWLEDGING AN INSTRUCTION TO HOLD SHORT.

Narrative: CAPT FLYING. WE LANDED ON RWY 21L AT DTW, CLRED TO HOLD SHORT OF RWY 21R ON TXWY FOXTROT. SWITCHED TO S GND; CTLR SAYS HE TOLD US TO HOLD SHORT OF RWY 21R. I BELIEVE I ACKNOWLEDGED THE HOLD SHORT INSTRUCTIONS, BUT NOT TOTALLY SURE. HOWEVER, I CONTINUED WITH MY AFTER LANDING FLOW. WHEN I LOOKED UP WE WERE CROSSING RWY 21R, THE CAPT AND I NOTICED A SAAB GOING AROUND RWY 21R, AFTER CROSSING THE RWY, GND TOLD US TO HAVE THE CAPT PHONE THE TWR WHEN WE GOT TO THE GATE.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.